Method for inducing electroanesthesia using high frequency, high intensity transcutaneous electrical nerve stimulation

ABSTRACT

A non-invasive method of treating, controlling or preventing medical, psychiatric or neurological disorders is provided using transcutaneous electrical stimulation. A plurality of stimulation frequency parameters are used ranging from a relatively high frequency, for example about 40,000 Hertz, to a relatively low frequency, for example about 250 Hertz. The entirety of frequency parameters may be administered at each of a plurality of stimulation intensity levels. In particular, stimulating may begin at a first highest frequency parameter and a first lowest intensity parameter with the stimulation frequency parameter incrementally decreasing to the lowest frequency parameter. Then the frequency parameter is returned to the highest frequency parameter, and the intensity parameter increased to a next higher intensity parameter, and again stimulating through the plurality of frequency parameters from the highest frequency to the lowest frequency. The method described herein is useful in treating, controlling and/or preventing various disease states and disorders, and has been found to be particularly effective in administering nerve block electroanesthesia.

This application is a continuation-in-part of U.S. Ser. No. 09/691,626,filed Oct. 18, 2000, abandoned, which was a continuation of U.S. Ser.No. 09/199,073, filed Nov. 23, 1998, now U.S. Pat. No. 6,161,044, thedisclosures of both of which are expressly incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to improved methods for the non-invasivetreatment of various disease conditions using an improved process oftranscutaneous electrical stimulation. In particular, provided hereinare improved methods of non-invasively treating symptoms of tremordisorders including essential tremors and tremors associated withParkinson's Disease; symptoms of dementia disorders including corticaldementia, such as is found in Alzheimer's disease and Pick's disease,subcortical dementia, such as is found in Parkinson's disease,Huntington's chorea and supranuclear palsy, and multi-infarct dementia;and symptoms of painful degenerative disorders, such as fibromyalgia andreflex sympathetic dystrophy by using transcutaneous electrical nervestimulation programs of variable intensity and variable frequency. Alsoprovided are apparatus for performing such methods.

BACKGROUND OF THE INVENTION

Transcutancous electrical nerve stimulation (TENS) is a well knownmedical treatment used primarily for symptomatic relief and managementof chronic intractable pain and as an adjunctive treatment in themanagement of post surgical and post traumatic acute pain. TENS involvesthe application of electrical pulses to the skin of a patient, whichpulses are generally of a low frequency and are intended to affect thenervous system in such a way as to suppress the sensation of pain thatwould indicate acute or chronic injury or otherwise serve as aprotective mechanism for the body. Typically, two electrodes are securedto the skin at appropriately selected locations. Mild electricalimpulses are then passed into the skin through the electrodes tointeract with the nerves lying thereunder. As a symptomatic treatment,TENS has proven to effectively reduce both chronic and acute pain ofpatients. However, TENS has shown no capacity for curing the causes ofpain, rather the electrical energy simply interacts with the nervoussystem to suppress or relieve pain.

The human nervous system essentially serves as a communication systemfor the body wherein information concerning the state of the body iscommunicated to the spinal cord (and/or brain) and behavioralinstructions are communicated from the brain (and/or spinal cord) to therest of the body. Thus, there are ascending neural pathways, such as theascending pain pathways, and descending neural pathways, such as thedescending inhibitory pathway (DIP), within the nervous system.

Briefly, pain impulses received by the free nerve endings of nociceptivenerve fibers (in particular, Aδ and C fibers) are conducted, throughvarious synapses, to the brain. In particular, these first order neuronsenter the dorsal horn of the spinal cord and synapse with second orderneurons, which are either relay cells, projecting into the brain stem orthalamus, or interneurons, synapsing to other interneurons or to relaycells. The second order neurons then (mostly) cross the spinal cord andbecome the anterolateral system, comprised of the neospinothalamic tract(or lateral spinothalamic tract) and paleospinothalamic tract. The nervefibers of the anterolateral system then terminate in various regions ofthe brain, including the brain stem, midbrain and thalamus.

Inhibition (or modulation) of pain, by the body, can occur anywhere fromthe point of origin of the pain through the successive synapticjunctions in the pain's central pathway. For example, following thedescending inhibitory pathways (DIP) of pain inhibition/modulation,stimulation in the cerebral cortex of the brain descends to the thalamusand then to the periaqueductal gray (PAG) of the midbrain. The PAGregion is rich in opiate receptors responsible for secretingmorphine-like enkephalins and endorphins. Nerve fibers from the PAG thendescend to the nucleus raphe magnus (NRM) in the brainstem. The NRM isresponsible for the secretion of serotonin, a compound that isinstrumental in elevating pain threshold levels and combatingdepression. Fibers from the NRM then descend into the spinal cord,synapsing with other inhibitory interneurons to cause secretion ofadditional powerful anti-pain neurotransmitters such asgamma-aminobutyric acid (GABA).

While prior art TENS devices and methods have been shown to be capableof affecting the ascending pathways of pain perception, they have shownlittle or no ability to affect the descending inhibitory pathways of thenervous system. The precise mechanisms by which these prior art TENSmethods operate to affect pain are not known; however, one theorysuggests that, by producing fast electrical waves that travel up the Aβnociceptive fibers, the TENS electrical stimulation pulses block painstimulus traveling up the Aδ and C fibers. One frequently reportedproblem with the prior art TENS methods is acclimation or accommodation;that is, the patient acclimates to the transcutaneous stimulation andthe pain returns. The intensity of the treatment, in such cases, isincreased to overcome the patient's accommodation of the treatment, butshortly, a maximum level of intensity is reached and further treatmentis ineffective.

A TENS simulator such as that shown in U.S. Pat. No. 5,052,391 is, ineffect, an electrical pulse generator which delivers electrical pulses(or impulses), transcutaneously, at a predetermined fixed or variablefrequency. Typically, TENS stimulators deliver electrical pulses atfrequencies in the range of about 50 to 200 Hertz (Hz). Most commonly,variable frequency TENS devices operate by beginning stimulation at thelowest frequency setting then increasing the frequency of stimulationuntil a pre-defined event occurs, such as motor nerve response orpatient comfort achieved. Such increases in frequency may be controlledby a doctor or other medical personnel or, more often, are controlled bythe patient him/herself. In addition to increasing the frequency of thestimulation pulses, the patient may be treated by simultaneouslyincreasing the intensity (or amplitude) of the stimulation output of thedevice.

For example, the patient may have a choice of different “levels” ofstimulation, each sequential level providing an increased frequency andintensity of stimulation as compared to the previous level. In eithercase, the output parameters generally start at their lowest level andare increased over the duration of the treatment.

Normally, when the patient (or other operator) increases the stimulationlevel of the TENS machine, in accordance with his/her doctor'sinstructions, the new, higher level is somewhat uncomfortable at first.However, as the patient knows from experience, his/her body accommodatesto the new higher level of stimulation within a tolerable length oftime. Once stimulation at one level becomes fully accommodated, that is,no longer works well to relieve the symptoms for which the treatment isbeing administered, the patient increases the stimulation level. Thus,as mentioned previously, the body is able to adjust to the electricalstimulation, requiring ever increasing levels of stimulation to achievethe same level of pain relief, often until no amount of stimulation iseffective. The use of devices of this general type for dental anesthesiais shown in U.S. Pat. Nos. 4,924,880 and 4,550,733. These devicesgenerally employed a biphasic symmetrical sinusoidal waveform at a peakvoltage of only 2 volts and a peak current of only 0.87 milliamps.

In some cases, the treatment frequency of the TENS device is fixed bydesign, or is established as a preselected, generally arbitrary, rate atthe time of treatment, and only adjustment of the intensity (oramplitude) of the electrical pulses is allowed. The typical intensitylevel of TENS stimulators is in the range of 30-200 volts. The waveformcharacteristic of the electrical pulses varies and includes, forexample, symmetrical sinusoidal waveforms, symmetrical biphasicwaveforms and DC needle spikes. Generally, the different waveforms arebelieved to offer some advantage over other waveforms; however, therehas been no clear consensus that any particular type of waveform isconsistently more advantageous than other types. What is known, however,is the general shape of the action potential waveform that isresponsible for producing electrical activity in neurons. Characteristicof this action potential are a very fast rise time and a slow decay.

The precise mechanisms by which transcutaneous electrical stimulationoperates to control pain are not known. When used to treat pain, thepatch electrodes of the TENS device are generally attached to thepatient in the vicinity of the pain. Thus, for example, in treatingjoint pain, electrodes would be affixed near the joint and stimulationadministered thereto. This localized stimulation then affects thenervous system to reduce the patient's perception of pain, presumably byeither affecting the pain signals being sent from the region to thebrain or by affecting the brain's perception of the signals it isreceiving from the region. Even the body's natural mechanisms forperceiving and affecting pain are poorly understood. However, it isknown that various biochemicals are released by nerve and brain cells inresponse to chemical and/or electrical stimulation of those cells. Theseneurotransmitters assist in the transmission of electrical messagesbetween and within the peripheral and central nervous systems.

In contrast to the TENS devices and methods used to affect the ascendingpathways of the nervous system, implantable electrical stimulators havebeen used to affect descending motor pathways of the nervous system.These electrical stimulators are surgically implanted into the patient'sbrain in order to affect, by direct electrical stimulation, specificregions of the brain. For example, by implantation of a stimulatingelectrode into the appropriate brain region, such as the thalamus and/orbasal ganglia, nervous activity within the brain can be affected and thesymptoms of movement disorders, such as akinesia, bradykinesia orrigidity and hyperkinetic disorders, can be reduced. See for exampleU.S. Pat. No. 5,716,377, Rise, et al., the entirety of which is herebyincorporated by reference. Thus, by stimulating the brain in thismanner, the skeletal muscles at the termination of the descending motorpathway are affected. Obviously, surgical implantation of an electrodeinto the brain, as well as direct electrical stimulation of the brainare risky procedures that are preferably utilized only in the mostextreme cases and after failure of less risky procedures.

Various disease conditions and disorders involve the brain and/ornervous system and thus may be amenable to treatment using drugs and/orelectrical stimulation. For example, U.S. Pat. No. 5,716,377, issued toRise, et al., Feb. 10, 1998, describes a method of treating movementdisorders by means of an electrode implanted into the brain of thepatient. Similarly, U.S. Pat. No. 5,713,923, issued to Ward, et al.,Feb. 3, 1998, describes a method of treating epilepsy using a brainimplanted electrode in combination with one or more drugs. While theeffects of electrical stimulation of certain specific nerves, specificnerve/brain regions and/or specific muscles to treat different diseasesand/or disorders have been described, few if any generalizations haveresulted therefrom. That is, it is still very difficult to predict whatif any type of nerve stimulation or drug therapy will work for any givendisorder.

Essential tremor (E.T.) is a movement disorder afflicting more than 5million people in the United States alone. This disease, which is themost common adult movement disorder, is about 20 times more prevalentthan the tremors associated with Parkinson's Disease and is a poorlyunderstood hereditary disorder. It is estimated that 32 in 1000 personsover the age of 60 years suffers from E.T. About 95% of those with thisdisease experience tremors, i.e. uncontrollable shaking, in both hands,often rendering the hands useless or near useless. Further, E.T. is theprimary cause of head tremors (Titubation), which tremors are not onlyextremely difficult to treat but arc particularly embarrassing anddebilitating. In particularly severe cases, E.T. patients have electedto undergo difficult and dangerous brain surgery wherein the part of thebrain responsible for the tremors is destroyed. Unfortunately, thissurgery can result in the unintended permanent impairment or destruction(i.e., paralysis) of movement speech and/or swallowing functions as wellas paraesthesia or tingling sensations in the patient's hands and/orhead.

The current treatment of choice for essential tremor is drug therapy.However, an estimated 60% of E.T. patients do not respond to drugtherapy and must therefore either live with the condition or resort tomore dangerous and more invasive forms of treatment. Even when drugtherapy is “successful,” it rarely results in diminution of headtremors; rather, only hand tremors may respond to the therapy. Further,the patient's body usually acclimates to the drug therapy, requiringincreased dosages of drugs, which, after time, become less effective.This necessitates frequent changes in drugs in order to obtain ormaintain the same level of relief.

Prior to 1997, in the U.S.A., the only alternative to drug therapy forthe relief of the symptoms of essential tremor was surgical destructionof part of the thalamus, from where the tremors are believed tooriginate. In 1997, (1995 in Europe), an implantable electronicstimulating device was approved for the treatment of essential tremor.This device is implanted deep into the thalamus of the patient andelectrical stimulation of that brain structure is used to control thetremor. However, the device is effective to control tremors onlyunilaterally, that is in only one hand. Further, the success rate of thedevice is not great, particularly given the invasive nature of theprocedure: with about 67% of 113 Parkinson's disease patients in onestudy experiencing control of tremors and about 58% of 83 essentialtremor patients in the study being relieved. Because almost allessential tremor patients suffer bilateral tremors (tremors in bothhands), those wishing to have the brain implant must choose which handto control, at least unless and until more than one implant may be usedsimultaneously, a procedure that to date has not been approved. Also,the brain implant has no effect on titubation (head tremor).

A prior art implantable brain stimulation device is described forexample in U.S. Pat. No. 5,716,377, issued to Rise, et al. andincorporated herein, in its entirety, by reference. This patentdescribes the use of an implantable device having the stimulatingelectrode implanted into the basal ganglia or thalamus of the patient,with the electrode lead passing under the skin of the patient to a pulsegenerator also implanted subcutaneously. Also described in the '377patent, is the implantable device including a sensor for sensing thetremors. The sensor is also implanted and is connected to the pulsegenerator. The brain stimulation device is operated at 0.1 to 20 voltsand at a frequency of between 2 to 2500 Hertz. Such devices areexpensive, about $10,000 for the device plus about $25,000 for therequired surgery, and require replacement of the pulse generator, andhence additional surgery and expense, about every three years.

Like essential tremor and Parkinson's disease, dementia disorders suchas Alzheimer's disease are primarily diseases of the brain. Alzheimer'sdisease is a degenerative disease in which nerve cells within the braindie and their connections deteriorate. It is the most common cause ofdementia and is the fourth leading cause of death among adults in theUnited States. While various causative factors have been postulated,such as heredity, environmental toxins and biochemical changes withinthe aging body, no specific cause for this disease had been identified.

Alzheimer's patients consistently have abnormally low levels ofneurotransmitters in their brains, particularly a neurotransmitter knownas acetylcholine. This reduction in neurotransmitters results in thegradual deterioration of the patient's mental processes and intellectualfunctioning, including memory loss, especially short-term memory,behavioral changes, inability to properly use language and the inabilityto perform skilled activities. Autopsies of Alzheimer's patients revealthe formation of protein plaques, comprised primarily of beta-amyloidprotein, within the critical memory and learning centers of the brain.Studies on rats have demonstrated that injection of substance P canblock the nerve damage caused by beta-amyloid, and thus, a significantportion of research efforts aimed at controlling this disease havefocused on this and other brain biochemicals.

Presently, there is no cure or prevention for Alzheimer's disease.However, two different drugs have been approved in the United States foruse in the management of this disease. While neither drug has beenproven to provide long term relief from the degenerative process ofAlzheimer's, at least one of the drugs has recently demonstrated anability to stop the decline in memory and alertness for 84% of patientsstudied for a six month period. Further this drug, known as Aricept(produced by Eisai, a Japanese company), does not apparently cause theliver-toxic side effects seen with the other approved drug. Thus,research on drug therapies for the treatment of Alzheimer's diseasecontinue.

Recently, the treatment of dementia disorders by electrical stimulationof specific cranial nerves has been described. U.S. Pat. No. 5,269,303,issued to Wemicke, et al., Dec. 14, 1993, describes stimulation of thevagus nerve to treat patients with dementia, and U.S. Pat. No.5,540,734, issued to Zabara, Jul. 30, 1996, describes stimulation of oneor both of the trigeminal and glossopharyngeal nerves to treat a varietyof neurological, medical and psychiatric disorders, including dementiadisorders. Each of these patents are hereby incorporated by reference intheir entirety. Unfortunately, however, these methods are premised uponimplantation of stimulation electrodes directly onto the specifiednerve. This not only means that the patient must undergo major surgeryto receive treatment, but also that the scope of treatment will belimited to the specific nerves upon which the electrode is implanted.Thus, once implanted, should the device not work to relieve the symptomsof the dementia or, worst, should the nerve stimulation result inintolerable side effects, either the device must be surgically explantedor must be deactivated and left within the patient's body.

Thus, what is needed is an inexpensive non-invasive method of treatingneurology-related disorders, such as dementia disorders and/or movementdisorders, that will be effective to relieve the very severe symptomsassociated therewith. In particular, with respect to movement disorders,such as essential tremor and tremors associated with Parkinson'sdisease, methods of providing relief for both bilateral hand tremors andhead tremors is needed. Similarly, with respect to dementia disorders,such as Alzheimer's disease, even a slowing of the deteriorationassociated with the disorders would be welcomed. Also desired is animproved way of creating nerve blocks through the use ofelectroanesthesia so as to provide a patient with localized comfort whenpain would otherwise be experienced.

SUMMARY OF THE INVENTION

The present invention addresses these and other objectives by providingmethods for the non-invasive treatment, control and/or prevention ofvarious disease conditions and disorders using transcutaneous electricalstimulation, wherein a plurality of stimulation intensities and aplurality of stimulation frequency parameters are employed such that theentire plurality of frequency parameters is administered, from highestto lowest frequency, at each of the plurality of stimulation intensityparameters. Further provided herein are apparatus for employing thesemethods.

In one aspect, the present invention provides improved results in thetreatment of various diseases by affecting the descending inhibitorypathways and neurotransmitter production and release within the nervoussystem. In particular, such results are achieved via transcutaneousnerve stimulation, a method which heretofore had not been described ordemonstrated, and which has also been found to be effective toadminister nerve block electroanesthesia.

In a preferred embodiment, the method contemplated herein, is useful totreat, control and/or prevent tremor disorders, such as essential tremorand tremors associated with Parkinson's disease, dementia disorders,such as Alzheimer's disease, and cortical, subcortical and multi-infarctdementia and painful degenerative disorders, such as fibromyalgia andreflex sympathetic dystrophy. This preferred method involves stimulatingat a first highest frequency parameter and lowest intensity parameter;decreasing the frequency parameter to the lowest frequency parameterover the course of time and in a specified manner, while holding theintensity parameter constant. The next stage in treatment is to increasethe stimulation frequency parameter back to the highest frequencyparameter but at a next higher stimulation intensity parameter. Thestimulation frequency parameter is then decreased in the same manner aspreviously done for the lower intensity parameter; while the intensityparameter is maintained at this next highest level.

The apparatus contemplated for use herein is a high frequency, highintensity transcutaneous electrical nerve stimulator (TENS) similar tothat described in U.S. Pat. No. 5,052,391 ('391 patent), issued toSilverstone, et al., the entirety of which patent is hereby incorporatedby reference. In a preferred embodiment, the TENS device described inthe '391 patent is modified to include a programmable microprocessorcapable of retaining and executing at least one, and preferably aplurality, of stimulation programs according to the new methodsdescribed herein and further is a digital device instead of analog asdescribed in the '391 patent. Most preferably then, the improved TENSdevice contemplated herein may be programmed to administer an entireregimen of therapy to a patient without requiring any control on thepart of the patient, while still permitting the patient the opportunityto control the device if desired. Further, the device will preferably beable to administer a plurality of treatment regimens, thereby beinguseful for a plurality of different disease states and disorders.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional aspects, features and advantages of the present inventionwill be apparent to those of skill in the art upon reading the followingdetailed description and referring to the accompanying drawings in whichlike numbers refer to like parts throughout and in which:

FIG. 1 is a block diagram of a preferred transcutaneous neurostimulatorfor use in accordance with the methods described herein.

FIG. 2 is a schematic of a frequency curve preferred for use in treatingtremor disorders;

FIG. 3 is a schematic of an alternative frequency curve, preferred foruse in treating dementia disorders and acute and chronic pain;

FIG. 4 is a schematic of an alternative frequency curve, preferred foruse in treating painful degenerative disorders, such as fibromyalgia andreflex sympathetic dystrophy; and

FIG. 5 is a schematic of an alternative frequency curve, preferred foruse in treatment of pain and induction of electronic nerve blockanesthesia and electroanesthesia.

FIG. 6 is a graph of results of neurochemical blood assays taken from apatient before, during and twenty-four hours following treatment inaccordance with the methods herein.

DETAILED DESCRIPTION OF THE INVENTION

The nervous system, including the brain, operates as a communicationnetwork for the body, carrying information and instructions from thebrain to the rest of the body, from the rest of the body to the brainand within the nervous system itself. In performing these functions, thenervous system and brain, among other things, use certain biochemicalmessengers, known as neurotransmitters, to accomplish this transferringof information and instructions. It has been known for some time thatelectrical stimulation of nerves, for example by implantation of astimulating electrode onto a particular nerve, can result in release ofone or more neurotransmitters from nerve cells thereby affecting theoperation of this communication system.

Numerous disease states and disorders involve the nervous system and/orbrain, many of which are believed to affect or result from the activityor lack of activity of neurotransmitters. For example, tremor disorderssuch as essential tremor and Parkinson's disease, dementia disorders,such as cortical dementia, as is found in Alzheimer's disease and Pick'sdisease, subcortical dementia, as is found in Parkinson's disease,Huntington's chorea and supranuclear palsy, and multi-infarct dementia;and painful degenerative disorders, such as fibromyalgia and reflexsympathetic dementia all involve the brain and/or nervous system and maybe related to neurotransmitter activity.

In preferred embodiments of the new methods described and claimedherein, transcutaneous electrical nerve stimulation techniques areemployed to treat, control and/or prevent these and other disorders.While the use of transcutaneous nerve stimulation for such purposes isnot unknown, the particular new methods described herein are uniquelyeffective. For example, in preferred embodiments, the methods describedherein result in increases in blood levels of neuro-transmitters, aheretofore unknown phenomenon. Most prior art transcutaneous nervestimulators operate by delivering electrical stimulation to the body ata moderately low to very low frequency and at a single level ofintensity. Usually, the patient is able to adjust either or both of thefrequency and intensity, but the device then stimulates for the durationof the treatment at only those selected parameters. In contrast, themethods presented herein operate by stimulating, in a defined pattern,at a plurality of frequencies beginning at a very high frequency andsweeping through the plurality of frequencies to the lowest frequency,while maintaining the intensity of the stimulation at a single lowintensity. Once a single sweep has been performed the intensity of thestimulation is incrementally increased and the entire frequency sweepperformed at the new higher intensity.

In general, the frequency ranges that are preferred for the methodsdescribed and claimed herein are from about 60,000 Hertz to 100 Hertz,and most preferably from about 40,000 Hertz to 400 Hertz. This is instark contrast to most transcutaneous electrical stimulating devices andmethods which operate in the range of about 50 Hertz to 200 Hertz.Preferably, the duration of treatment at a single level of intensity,that is the time spent stimulating through a single sweep of frequencyparameters, is 1 to 30 minutes. More preferably, the time is 1-20minutes and most preferably 1-15 minutes. The range of acceptablestimulation intensities is not critical, but is generally from aboutzero to 100 volts, and in preferred embodiments is zero to 60 volts. Thepreferred stimulating device operates at about 40 mamps, but this too isnot critical. What is important is that the general method of sweepingthrough the entire plurality of frequency parameters, along thefrequency curve, occur for at least two sequentially increasing levelsof intensity. Thus, for example, in a most preferred embodiment, asdescribed further below, the maximum output voltage (intensity) of thedevice is equally divided into ten different intensity parameters (orlevels); such as 5.7 volts at the lowest parameter (level 1), 10.4 voltsat the second parameter (level 2), and so on up to 57 volts at thehighest intensity parameter (level 10). While not all intensity levelsare necessarily used in a single treatment program, those levels thatare used are used for an entire, single sweep of the frequency curve.

Turning then to FIG. 1, illustrated is a block diagram of a preferredtranscutaneous neurostimulator for use in practicing the improvedmethods described herein. This preferred transcutaneous nervestimulation apparatus has digital frequency generation and provides twoindependent channels of bipolar, variable frequency, variable amplitude,and patient output signals. These output signals are coupled to thepatient via skin electrodes, preferably two per channel. The frequencyand amplitude of the outputs are preferably adjustable via front panelswitches, or, in the case of frequency, also by a hand-held remotecontrol. LED numeric and bar graph displays on the front panel may beused to provide the operator with a visual indication of amplitude(intensity) and frequency (bias) settings. The device is preferablybattery powered and microprocessor controlled. Thus, the preferredapparatus is, conceptually, a two channel, variable frequency, variableamplitude, square wave frequency generator. As discussed in detailbelow, the apparatus preferably commences its operations at a highestfrequency output and is reduced at a predefined rate, to a lowestfrequency as other output parameters are increased (amplitude &current). This frequency sweep is preferably repeated over each of tenincreasing intensity levels.

Preferably, the transcutaneous stimulator apparatus contemplated for useherein has five input/output connectors mounted on the back of theapparatus enclosure. These include, for example, an output connector foreach channel, an input connector for battery charging, an inputconnector for the remote hand-held controller, and outputs for thetreatment recorder. The battery employed in the apparatus is preferablya 12 volt, rechargeable gel cell. It supplies power for the entiresystem. It is recharged by connecting a wall mount charger to thecharger input connector. Such a battery generally has a life of severalhours depending, somewhat, upon the bias and amplitude settings used bythe patient, as well as upon the individual patient load.

As contemplated herein, the front display of the apparatus is a membraneswitch overlay with “smoked” transparent windows to allow displayviewing. Displays include, for example, eight LED numeric digits and two10 element LED bar graphs, with the following variables preferably beingdisplayed: Channel 1 Intensity (2 digits plus decimal); Channel 1 Bias(2 digits plus decimal plus 10 bars); Channel 2 Intensity (2 digits plusdecimal); and Channel 2 Bias (2 digits plus decimal plus 10 bars). Twoadditional LED elements are also preferably included on the front paneldisplay, one indicating “Power On” and the other indicating “BatteryCharging”. Each channel preferably has five control switches: channelOn/Off; Intensity Up; Intensity Down; Bias Up; and Bias Down. Themembrane switch panel connects to the display board, which in turnconnects to the microprocessor board. Via this connection, themicroprocessor can detect when a front panel switch closure occurs andappropriately control the displays and patient output.

As shown in FIG. 1, a microprocessor board 20, containing the majorityof the circuitry, is provided. The microprocessor 20 may be, forexample, an 8 bit Motorola 68HC 11 device utilizing external EPROM 22for program memory. The EPROM 22 memory preferably is about 8K bytes andis interfaced to the processor with an address latch and appropriatestrobe decode logic. The processor clock preferably operates at about 8MHZ and is crystal controlled. The processor communicates with theremaining circuitry via input/output ports, one of which includes aninternal analog to digital converter. When the unit is switched on, theprocessor is momentarily at rest and then begins fetching and executinginstructions from the EPROM memory. As long as the unit is switched on,the processor is running (fetching and executing instructions). The mainfunctions of the processor are to read the operator control switches andremote hand-held controller, adjust the amplitude and frequency of theoutputs, and send related data to the display board for display.

In the preferred embodiment, the On/Off switch and the emergency shutdown switch relay 24 are in series with the positive pole of the 12 voltbattery. Thus, when either of these switches are Off, no battery currentflows to the microprocessor board. When On, 12 volts DC is supplied tothe microprocessor board. The emergency shut down switch circuit employsan SCR to latch the relay in or out. Thus, once tripped this circuit isonly reset by turning the main power off and then back on again.

The 12 volts is supplied primarily to three areas: a 5 volt regulator26; a DC step up regulator 28; and a low battery detection circuit 30.

The 5 volt regulator 26 can be a standard linear, series, in-lineregulator. The output is then a regulated 5 volts and provides theoperating power supply for the majority of the circuitry(microprocessor, memory, display board, etc.). The DC step up regulator28 is an inductive switching regulator used to increase the 12 volt DCinput to an approximately 40 volt DC output. The switching regulatoroscillates at a high frequency, varying with load. On one cycle of theoscillation, current passes through the inductor building up a magneticfield. On the alternate cycle the field collapses, inducing a highvoltage which is stored in a large capture capacitor. The capturecapacitor positive pole is the 40 volt output point and is fed back tothe switching regulator circuit to cause a closed loop regulation ofthis voltage. The switching regulator varies frequency and duty cycle inorder to maintain the output at 40 volts DC. This 40 volts is the supplyvoltage for the output stage intensity control amplifiers. A low batterydetection circuit 30 is also provided. It determines when the 12 voltbattery drops below a predetermined value, then trips the hardwareinterrupt on the processor and forces it to transition to a safe stateand shut down. In addition, this is signaled to the operator bydisplaying “bA Lo” or similar informative message, on the display board52.

One of the main functions of the processor is to monitor the user remotecontrol 32 and front panel switches 34. The user remote control 32 ispreferably a simple linear, slider potentiometer. It is connected acrosspower (5+volts) and ground with its wiper forming the output. Thus, itsoutput is a DC voltage somewhere between +5 volts and ground dependingon wiper position. This signal is fed into an analog to digitalconverter input on the microprocessor. The A/D converter preferably hasa resolution of 8 bits. Thus, the DC 0 to 5 volt input is converted to adigital number 0 to 255. This is then used by the processor to controlthe output bias setting (frequency). It should be noted that bias andfrequency are inversely related; that is, a bias of 0.0 results in thehighest frequency and a bias of 9.9 is the lowest frequency.

Each of the ten front panel switches are connected to an individualmicroprocessor port. The other side of all switches are connected tosystem ground. Also connected to each port is a pull up resistor to +5volts. Thus, when the switches are open (unpressed), the port pins sitat +5 volts. When a switch is pressed, its associated port pin is forcedto ground (0 volts). During operation of the preferred apparatus, theprocessor continually monitors these port pins, looking for a key pressor change in remote control slider position. When detected, theappropriate action is taken.

A second important function of the processor in this preferred apparatusis to control the bias (frequency) and intensity (amplitude) of theoutputs. The outputs are transformer-coupled to the patient. The patientis connected to the secondary side of a 1: 1 transformer 46, 48 (one perchannel). One lead of the primary side of the transformer is connectedto the intensity drive circuitry 36, 38 and the other lead is connectedto the bias drive circuitry 40, 42. The intensity drive circuitry 36, 38is merely a DC voltage amplifier whose input in 0 to 5 volts, which istranslated to 0 to 40 volts on the output. The input signal comes from adigital potentiometer 44 which is under control of the microprocessor20. Thus, the processor 20 sends a digital byte to the digitalpotentiometer 44. The potentiometer 44 converts this into a voltagebetween 0 and 5 volts depending on the intensity setting. The intensitydrive circuitry 36, 38 converts this into a voltage between 0 and 40volts, which appears on one end of the transformer 46, 48 primary.

The bias drive circuitry 40, 42 is preferably a transistor power switchwhich pulls the other end of the transformer primary 46, 48 to groundwhen it is on, or lets it float (unconnected) when it is off. Thus whenthis switch is on, current flows through the primary at a leveldetermined by the intensity setting (0 to 40 volts). When this switch isoff, no current flows through the primary. The input to the bias drivecircuitry is preferably a square wave created by a dual channelprogrammable timer 50. The timer is connected to the processor/memorybus and is programmed by the processor 20 to create a specific squarewave frequency based on bias setting. The microprocessor “E Clock” formsthe clock signal for the programmable timer (2 MHZ) 50. Thus, theprocessor 20 determines bias setting from front panel 34 switch pressesand hand controller position 32. Using the bias setting the processor 20determines desired frequency from a currently selected frequency look uptable within the processor. The processor 20 then outputs the necessarycommands to the programmable timer 50 to create a specific frequencyoutput. It should be noted that since the frequency base to the timer is2 MHZ, the resolution of frequency period is 0.5 micro seconds. Thesquare wave output from the timer 50 then drives the digital switchwhich causes current to flow on and off, at the desired frequency,through the transformer primary. In other words, on one side of thetransformer primary is a DC voltage, 0 to 40 volts, set by intensity; onthe other side of the primary is an on/off switch, operating at the biassetting frequency. The processor 20 also preferably has an over riding“stop” line (not shown) to each channel which can force the bias drivecircuitry off. In addition, while monitoring the hand controller 32 todetermine bias setting the processor computes rate of change of handcontroller position 32. If this rate of change exceeds a preset limit anerror is detected and the outputs are switched off. This permitsdetection of, for example, a hand controller broken ground wire, or anaccidentally moved (bumped) hand controller.

The display board 52 contains all the light emitting diode (LED) numericand bar graph displays 54 in addition to the display drivers 56 and twoinput/output connectors (not shown). One connector mates with themembrane switch panel to bring front panel switch connections into thesystem. The other connector connects to a 20 pin ribbon cable whichconnects in turn to the microprocessor board. Power for the displayboard, front panel switch signals, and LED drive signals all flowthrough this ribbon cable.

Finally, in this most preferred embodiment of the apparatus, there arethree driver integrated circuits on the display board. These providedirect drive for all the bar graph and numeric LED displays on theboard. These drivers form a serial data link to the processor via theribbon cable. Thus, the processor decides which LED's should be on andshifts out the appropriate serial data word to effect this. To conservebattery life the LED's are multiplexed on a 50% duty cycle, that is, atany one time, only half the LED's are on. This multiplex rate is fasterthan the human eye can perceive and thus the appearance is that alldisplays are constantly illuminated. To further conserve battery powerthe bar graph is preferably lighted in a climbing, one bar-at-a-timemode. All of the numeric, multiplexing, and bar graph decodingpreferably takes place in the processor 20 under software control. Thedrivers merely turn on LED's bit for bit as instructed by the processor

Referring now to FIG. 2, illustrated is a frequency curve preferred foruse in treating tremor disorders, such as essential tremor and tremorsassociated with Parkinson's disease. It is this same curve, then, thatis used at every intensity level at which stimulation is provided to thepatient. Thus, at each intensity level, a range of stimulationfrequencies is provided to the patient, beginning at about 40,000 Hz anddecreasing to about 400 Hz, at the rate indicated by the frequency curveillustrated in FIG.2. The following detailed example is illustrative ofa preferred treatment process for tremor disorders.

First, two pair of self-adhesive electrodes are affixed to the patient'sskin. Suitable electrodes are well known to those of skill in the art,for example Bio-Skin Silver electrodes (Synaptic Corp., Aurora, Colo.).One pair is placed bilateral to the spine at C6, with approximately oneinch between the inner medical borders of the electrodes. The secondpair is affixed bilateral to the spine at L5, also spaced about one inchfrom one another as measured at the inner medical borders. Both pairs ofelectrodes are operatively attached to the electrical stimulator (i.e.pulse generator), which is most preferably preprogrammed with thedesired treatment program thereby permitting the doctor, other medicalor lay personnel or the patient his/herself to very easily activate theprogram. The next step is to turn on the electrical stimulator and beginthe treatment program.

Generally, when the method is employed to treat, control or prevent adisorder selected from the group consisting of essential tremor andParkinson's disease and wherein the step of incrementally decreasing thestimulation frequency parameter is performed for a time duration (T),one may employ the following sequential steps of a) steadily decreasingthe stimulation frequency parameter about 70% over the time period 0.1T;b) steadily decreasing the stimulation frequency parameter about 5% overthe time period 0.1T; c) steadily decreasing the stimulation frequencyparameter about 20% over the time period 0.7T; and d) steadilydecreasing the stimulation frequency parameter the remaining about 5%over the remaining time period of 0.1T, wherein the percentages are ofthe total frequency parameter range from the lowest frequency parameterto the highest frequency.

Electrical stimulation preferably begins at the highest stimulationfrequency and lowest stimulation intensity for the programmed treatment.As illustrated in FIG. 2, the highest, and therefore initial,stimulation frequency is preferably about 40,000 Hz for treatment oftremor disorders. Preferably, the frequency curve of FIG. 2 isadministered in a plurality of individual stimulation frequencyparameters, and most preferably in about 100 different frequencyparameters. These 100 different stimulation frequency parameters may,for example, be numbered as 0.0 through 9.9 (or 0.1 through 10.0).Preferred settings for some of the 100 points along the frequency curveillustrated in FIG. 2 are as follows:

TABLE C Frequency Parameter Number Frequency (Hz) 0.0 40,000 0.5 21,0001.0 10,000 1.5 9,100 2.0 8,500 2.5 8,000 3.0 7,500 3.5 6,500 4.0 6,0004.5 5,500 5.0 5,000 5.5 4,500 6.0 4,000 6.5 3,500 7.0 3,000 7.5 2,5008.0 2,000 8.5 1,500 9.0 1,000 9.5 500 9.9 400

It is preferred to use at least about ten intensity levels, wherein thetotal output voltage available is equally divided among the ten (ormore) levels. The maximum voltage output is not critical, but ispreferably in the range of about 40-150 volts, and most preferably about50-100 volts, peak to peak. A preferred tremor treatment program, inaccordance with the present invention is about 45 minutes in duration,delivers stimulation according to the above described frequency curveand employs all 10 intensity levels according to the following schedule:

Intensity Level Time (minutes) 1 1 2 2 3 2 4 4 5 4 6 4 7 4 8 8 9 8 10 8

At each intensity level, only one sweep of the stimulation frequencycurve is performed. Thus, for example, at the lowest intensity level,level one, the stimulation frequency is reduced in one minute from about40,000 Hz to about 400 Hz, following the curve illustrated in FIG. 2;whereas at intensity level 10, the highest intensity level, thestimulation frequency preforms the same pattern of decreasing from40,000 to 400 Hz, but does so in eight minutes.

A patient, D.P., was treated in the manner just described, except thatthe highest stimulation frequency used was 30,000 Hz. D.P. had a tenyear history of essential tremor. He suffered bilateral hand tremors. Inhis left hand, the tremors were so bad he could not touch his nose.While various drugs had brought D.P. some relief over the years, theyslowly became ineffective, even at very high doses. D.P. was not asuitable candidate for implantation of a brain stimulator and thus,agreed to undergo this experimental transcutancous electricalstimulation program. After his first 45-minute treatment, he remainedtremor-free for four (4) hours. Daily treatments for the subsequent 14days provided complete cessation of his tremors over each 24 hourperiod. D.P. has been receiving such treatment for over a year, and histremors are still well controlled, despite receiving treatment onlyabout three times a week. He has described the severity of his tremorsas a 2 on a scale of 1-10 with 10 being the most severe tremors, and 1being tremor-free.

Since beginning treatment on D.P., other patients suffering with tremordisorders have been treated on an experimental basis. The results, todate, have been consistent with those observed in D.P. Both bilateralhand tremors and head tremors (titubation) have been successfullytreated using this new method and device. This is in stark contrast tothe brain implant devices which have only been demonstrated useful incontrolling tremors in one hand and not at all in the head. It is notedthat, preferably, the patient (or doctor or other medical or laypersonnel controlling the electrical stimulation) may stop theelectrical stimulator at any time by pushing a single button. Thiscontrol is important so that the patient does not experience unnecessarypain or discomfort during treatment.

It is believed that among other things, the general method oftranscutaneous electrical stimulation described and claimed hereinmodulates both the ascending and descending pathways of the nervoussystem resulting in the release of neurotransmitters that then favorablyaffect the brain to control the symptoms of the disease being treated.In the case of treatment of tremor disorders, for example, it isbelieved that the thalamus and Basal Ganglion (the thalamocorticalcircuits) are stimulated by this method to provide control of bothbilateral tremors and head tremors.

FIGS. 3-5 each illustrate alternative, preferred frequency curves fortreating various disease states and disorders. For example, FIG. 3illustrates a frequency curve particularly useful for treating dementiadisorders. FIG. 4 illustrates a frequency curve particularly suited totreatment of painful degenerative disorders such as fibromyalgia andreflex sympathetic dystrophy, and FIG. 5 is particularly useful forinducing electroanesthesia.

As with the method described above for treating tremor disorders, inpreferred embodiments, the frequencies represented by these curves areadministered as a plurality of frequency parameters and most preferablyare administered as about 100 frequency parameters. Also in accordancewith the general method of the present invention, a plurality ofstimulation intensities are employed and the entire plurality offrequency parameters are administered at each intensity level.

For example, in treating a patient suffering with a dementia disorder,such as Alzheimer's disease, the patient first has two pairs ofelectrodes affixed to the skin in about the same location as describedfor treatment of tremor disorders; that is bilateral to the spine at C6and L5. The leads of the electrodes are operatively connected to theelectrical stimulator and the appropriate program initiated. As with thetremor treatment described above, the stimulation program to be used fortreating the dementia patient is most preferably preprogrammed so thatno adjustment thereto need be made by the patient (other than, ofcourse, termination of the treatment should such be desirable ornecessary). Once the electrodes are properly affixed to the patient andthe leads connected to the electrical stimulator, the unit is switchedon.

Generally, when the method is employed to treat, control or prevent adisorder selected from the group consisting of Alzheimer's disease,cortical dementia, subcortical dementia and multi-infarct dementia andwherein the step of incrementally decreasing the stimulation frequencyparameter is performed for a time duration (T), one may employ thefollowing sequential steps of a) steadily decreasing the stimulationfrequency parameter about 66% over the time period 0.1T; b) steadilydecreasing the stimulation frequency parameter about 23% over the timeperiod 0.2T; c) steadily decreasing the stimulation frequency parameterabout 5.5% over the time period 0.1T; and d) steadily decreasing thestimulation frequency parameter the remaining about 5.5% over theremaining time period of 0.6T, wherein the percentages are of the totalfrequency parameter range from the lowest frequency parameter to thehighest frequency.

As previously described, stimulation always begins at the higheststimulation frequency parameter and lowest stimulation intensity. Theprogram then decreases the stimulation from the highest frequencyparameter, in this case, preferably about 40,000 Hz, to the lowestfrequency parameter, preferably 400 Hz, in accordance with the frequencycurve illustrated in FIG. 3. It is preferred that about 100 differentfrequency parameters be used. The following table provides settings forsome of the 100 points along the frequency curve illustrated in FIG. 3:

Frequency Parameter Number Frequency (Hz) 0.0 40,000 0.5 21,000 1.012,000 1.5 10,000 2.0 8,000 2.5 6,050 3.0 4,100 3.5 3,175 4.0 2,250 4.52,017 5.0 1,785 5.5 1,556 6.0 1,325 6.5 1,162 7.0 1000 7.5 900 8.0 8008.5 700 9.0 600 9.5 500 9.9 400

A preferred treatment program for Alzheimer's disease, according to thepresent invention, involves slowly stepping up the maximum intensity ofthe stimulation over the course of several treatments. Thus, forexample, during the first one-hour treatment administered to thepatient, the stimulation intensity is raised only to level 7 of 10(which is preferably 70% of the highest available intensity level). Theone-hour treatments are preferably administered once a day, and thisfirst level of treatment (i.e., wherein the maximum stimulationintensity is only 70% of the highest available intensity level) ispreferably carried out for about the first ten days (or first tenone-hour treatments). The second level of treatment, preferablyconducted for the 11^(th)-20^(th) of the daily treatments, increases themaximum intensity level to 8 (80% of the highest available intensitylevel). Treatments 21-30 provide a maximum intensity level of 9 (90%),and the remaining treatments include the highest available intensitylevel (10). The following table shows each of the four different levelsof treatment with the number of one-hour treatments to be performed atthat treatment level (in parentheses) and provides the duration ofstimulation at each intensity level within each different level oftreatment:

Level 1 Level 2 Level 3 Level 4 (1-10) (11-20) (21-30) (31-) Inten-Inten- Inten- Inten- sity Time sity Time sity Time sity Time Level (min)Level (min) Level (min) Level (min) 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 3 43 4 3 4 3 4 4 8 4 8 4 8 4 8 5 15 5 10 5 8 5 8 6 15 6 10 6 8 6 8 7 15 710 7 9 7 8 8 15 8 10 8 8 9 10 9 8 10 5

While a specific rate for moving through the four levels of treatment isprovided, this is meant to be illustrative only. Individual patientswill tolerate the sensations associated with the transcutaneousstimulation differently. This is particularly of concern when dealingwith Alzheimer's patients or other patients suffering from dementia,because such patients may be unable to communicate their level ofcomfort or discomfort clearly. Thus, the above schedule of treatment isintended as a guide. In practice, the doctor or other medical or laypersonnel operating the device should closely monitor the patient forindications that he/she is becoming uncomfortable with the intensity ofstimulation being administered. As with all the devices contemplatedherein, it is preferred that the stimulation device include a simplemechanism for terminating stimulation, should such be desirable ornecessary.

FIG. 4 illustrates a frequency curve preferred for use in treatingpainful degenerative disorders such as fibromyalgia and reflexsympathetic dystrophy, as well as general acute and chronic pain.Fibromyalgia is a widespread musculoskeletal pain and fatigue disorderfor which the cause is still unknown. Most patients with fibromyalgiacomplain of systemic pain, often described as deep muscular aching,burning, throbbing, shooting and stabbing pain. No routine laboratorytesting is available for diagnosing this debilitating disorder. Uponphysical examination, patients are usually sensitive to pressure incertain areas of the body. Currently, diagnosis is made based solely onestablished criteria relating to the severity, widespread locality andduration of the pain.

Reflex sympathetic dystrophy (RSD) is a very severe form of chronic painbelieved to affect as much as 10% of the entire population. The chronicpain of this syndrome is typified by a marked emotional connotation,such as severe anxiety, phobia and/or neuropsychological disturbances inthe form of sever irritation, agitation and depression.

As with the specific examples given above for treatment of tremor anddementia disorders, treatment of fibromyalgia, RSD and similar painfuldegenerative disorders involves the administration of transcutaneouselectrical stimulation beginning at a highest frequency parameter andlowest stimulation intensity level; decreasing the frequency parameterto a lowest frequency parameter by stimulating at a plurality ofstimulation frequency parameters therebetween; then increasing thestimulation intensity level to a next highest intensity level andincreasing the frequency parameter back to the highest parameter,followed by repeating the pattern of decreasing the frequency parameterto the lowest parameter. In a most preferred embodiment of treatingthese degenerative disorders, illustrated by the frequency curve of FIG.4, the highest stimulation frequency parameter is 40,000 Hz and thelowest frequency parameter is 2,500 Hz. As with the previously describedexamples, the maximum output voltage is preferably divided into tenlevels.

Generally, when the method is employed to treat, control or prevent adisorder selected from the group consisting of fibromyalgia, reflexsympathetic dystrophy, general acute pain and chronic pain and whereinthe step of incrementally decreasing the stimulation frequency parameteris performed for a time duration (T), one may employ the following stepsof a) steadily decreasing the stimulation frequency parameter about 66%over the time period 0.1T; b) steadily decreasing the stimulationfrequency parameter about 13% over the time period 0.1T; c) steadilydecreasing the stimulation frequency parameter about 6% over the timeperiod 0.1T; d) steadily decreasing the stimulation frequency parameterabout 5% over the time period 0.2T; and d) steadily decreasing thestimulation frequency parameter the remaining about 10% over theremaining time period of 0.5T, wherein the percentages are of the totalfrequency parameter range from the lowest frequency parameter to thehighest frequency.

Thus, the following table provides several frequency parameters takenfrom the frequency curve illustrated in FIG. 4. As with the similartables provided herein, the frequency parameters are preferably numbered0.0 through 9.9, providing 100 different frequency parameters:

Frequency Parameter Number Frequency (Hz) 0.0 40,000 0.5 21,000 1.012,000 1.5 9,875 2.0 7,750 2.5 6,775 3.0 5,800 3.5 5,275 4.0 4,750 4.54,375 5.0 4,000 5.5 3,760 6.0 3,520 6.5 3,360 7.0 3,200 7.5 3,100 8.03,000 8.5 2,850 9.0 2,900 9.5 2,600 9.9 2,500

Preferably, total treatment times are about 20 minutes and are, ideally,administered several times a week. However, weekly treatments have beendemonstrated to provide noticeable favorable results. As with othertreatments described herein, the treatment program typically begins withmore time spent at lower intensities, gradually increasing the durationof stimulation at higher frequencies in subsequent treatments.

FIG. 5 illustrates a final exemplary frequency curve for use inaccordance with the present invention. The frequency parameterscomprising this curve have been found to be particularly useful ininducing electroanesthesia and nerve block anesthesia, as well as forthe general treatment of pain. The following table provides exemplaryfrequency parameters taken from the curve illustrated in FIG. 5:

Frequency Parameter Number Frequency (Hz) 0.0 40,000 0.5 25,500 1.011,000 1.5 9,500 2.0 8,000 2.5 7,000 3.0 6,000 3.5 4,750 4.0 4,500 4.54140 5.0 3,775 5.5 3,410 6.0 3,050 6.5 2,690 7.0 2,325 7.5 1,960 8.01,600 8.5 1,300 9.0 1,000 9.5 700 9.9 400

It will be apparent that where nerve block anesthesia (orelectroanesthesia) is the goal, a single “treatment” is preferablyperformed. Generally, one pair of smaller electrodes, for example about1.25 inches in diameter, are placed in the vicinity of the nerve to beblocked about 1 inch apart. A second pair of larger electrodes, forexample about 2 inches in diameter, are placed about 1 inch apart eitherbilateral the spine at about C5 or on the opposite side of the body fromthe location of the first electrode pair. Stimulation is begun at arelatively high intensity and is manually increased as high as isreasonably tolerable to the patient, usually to a level of about 70%-90%of 60v maximum intensity of the neurostimulator described hereinbefore,i.e. about 40 to about 55v. The waveform employed has a fast rise timeand a slow decay, which has been found to provide a particularlyadvantageous biological approach in that it stimulates the ActionPotential responsible for producing electrical activity in humanneurons. The intensity is then held at that level while the stimulationfrequency is decreased to a lower frequency. The original decrease infrequency may be carried out in a manner that can be accommodated by thepatient to reach an initial tolerable stimulation level, with thefrequency level being decreased increment by increment thereafter.Alternatively, the program is used which is set to sweep through aplurality of frequencies in accordance with the curve set forth in FIG.5 that is depicted in the table set just above, usually for a period ofat least about 20 minutes and often from 20 to 30 minutes. It is notedthat, either a single frequency parameter sweep may be performed or atthe end of a first sweep, the treatment may be repeated at a next higherintensity level.

Generally, when the method of treatment is employed to create a nerveblock by electroanesthesia, one may incrementally decrease thestimulation frequency parameter for a time duration (T) as exemplifiedin FIG. 5 by employing the following steps of (a) continuouslydecreasing the stimulation frequency about 73% of the first highfrequency over the first time period 0.1T; (b) continuously decreasingthe stimulation frequency about another 8% of the first high frequencyover the next time period 0.1T; (c) continuously decreasing thestimulation frequency about another 5% of the first high frequency overthe next time period 0.1T; (d) continuously decreasing the stimulationfrequency about another 4% of the first high frequency over the nexttime period 0.1T; and (e) continuously decreasing the stimulationfrequency about another 10% over the remaining time period of 0.6T.

As can be seen from the Figures herein, the frequency curves have asimilar basically logarithmic shape. Association of specific frequencyparameters and curve slopes with a specific disorder is preferablydetermined by clinical evaluation. In fact, the different curvesexemplified herein are useful for treating other diseases and disorders.Thus, it is the particular manner of stimulating described herein thatmakes these methods particularly effective, that is the stimulatingmanner of sweeping through the same set of frequency parameters from ahigh frequency parameter of, for example, 40,000 Hz, to a low frequencyof, for example 400 Hz, at each of a plurality of incrementallyincreasing stimulation intensities.

It is believed that the required initial stimulation at a high frequencycauses rapid depolarization of the cell permitting ideal functioning ofthe so stimulated neurons. Whereas prior art TENS devices and methodsare believed to stimulate only the large Aβ fibers of the nervoussystem, it is believed that the present method results in stimulation ofthe Aδ and C fibers as well as the Aβ fibers, by providing stimulationwaveforms that closely mimic natural action potential waveforms and/orpiggyback on such waveforms. Increases in circulating blood levels ofvarious neurotransmitters, such as norepinephrine, serotonin,epinephrine, ACTH and beta endorphins, provide evidence of this mode ofoperation.

As seen in FIG. 6, in one patient, suffering with chronic pain, thelevels of various neurotransmitters not only increased during the 20minute treatment provided, but continued to measurably increase for the24 hours following such treatment. Note that the y-axis scale on thegraph in FIG. 6 is relativistic. Levels of the neurotransmitters aremeasured in pg/ml for epinephrine and norepinephrine, in pmol/l forACTH, in ng/ml for serotonin and in pg/0.1 ml for beta endorphin. Thus,the graph should be used to compare levels of a single neurotransmitterover time not to compare levels among neurotransmitters. Thus, byproviding electrical stimulation at a central location on the body, inaccordance with the methods detailed herein, the body's natural healingmechanisms are systemically stimulated to relieve the symptoms of thenerve-related disease condition being treated.

The examples provided herein are of specific embodiments only and arenot intended to limit the scope of the claims appended hereto. Those ofskill in the art will recognize that the preferred embodiments describedherein may be altered or amended without departing from the true spiritand scope of the invention, as defined in the following claims.

What is claimed is:
 1. A non-invasive method of inducing nerve blocks byusing electroanesthesia applied via transcutaneous electricalstimulation, which method comprises affixing a first electrode pair tothe skin of a patient to be treated in the vicinity of the nerve to beblocked, which electrode pair is associated with a pulse generator suchthat stimulation at a desired frequency and intensity may be provided tothe patient through said electrode pair, affixing a second electrodepair to the skin of a patient either on the opposite side of the bodyfrom the location of the first electrode pair or bilaterally of thespine at about C5, said second electrode pair being larger in size thansaid first electrode pair and also being associated with the pulsegenerator, and thereafter carrying out the following steps of: (a)providing the patient with a series of intensities at which stimulationmay be carried out; (b) choosing an intensity from said series as highas the patient can reasonably tolerate; (c) stimulating at a first highfrequency in the range of 60,000 Hz to about 25,000 Hz and at saidchosen intensity; and (d) decreasing the stimulation frequency at saidchosen intensity to a lower frequency over a time period of at leastabout 20 minutes by initially lowering the frequency to a level that isstill tolerable to the patient and then continuing to gradually decreasethe frequency thereafter.
 2. The method of claim 1 wherein said firsthigh intensity is between about 55 and about 40 volts.
 3. The method ofclaim 2 wherein the first high frequency parameter is about 40,000 Hertzand the lowest frequency parameter is not less than about 250 Hertz. 4.The method of claim 2 wherein said first high intensity is at anamperage of about 40 milliamps.
 5. The method of claim 2 wherein saidstimulating employs a waveform having a fast time rise and a slow decay.6. The method of claim 2 wherein the first high frequency parameter isabout 40,000 Hertz and the lowest frequency parameter is not less thanabout 400 Hertz.
 7. The method of claim 1 wherein said second electrodepair is located bilateral of the spine at C5.
 8. The method of claim 1wherein said decreasing of the stimulation frequency is performed over atime duration (T) of at least about 20 minutes and comprises the stepsof: a) decreasing the stimulation frequency about 73% of the first highfrequency over the first time period 0.1T; b) then decreasing thestimulation frequency about another 8% of the first high frequency overthe next time period 0.1T; c) then decreasing the stimulation frequencyabout another 5% of the first high frequency over the next time period0.1T; d) then decreasing the stimulation frequency about another 4% ofthe first high frequency over the next time period 0.1T; and e) thendecreasing the stimulation frequency about another 10% over theremaining time period of 0.6T.
 9. The method of claim 8 wherein thefirst high frequency parameter is about 40,000 Hertz and the lowestfrequency parameter is not less than about 400 Hertz.
 10. The method ofclaim 9 wherein said first high intensity is between about 55 and about40 volts at an amperage of about 40 milliamps.